New record of Ixodes pavlovskyi (Acari: Ixodidae) from the Osaka Prefecture, western Japan: An update on the southernmost distribution record.

Ixodes pavlovskyi inhabits cool temperate zones, especially in Russia, north-eastern China and northern Japan. This tick species is thought to transmit various pathogens such as Borrelia spp., Rickettsia spp. and tick-borne encephalitis virus. Hence, understanding the geographical distribution of I. pavlovskyi is important for estimating risk of tick-borne diseases. Among ticks collected using the flagging method in Osaka Prefecture, south-western Japan, we found a single I. pavlovskyi male that was identified based on its morphological features and the mitochondrial 16S rDNA sequence. To the best of our knowledge, the finding of I. pavlovskyi in Osaka Prefecture, highly humid subtropical western Japan, is the southernmost record of this species. Although ticks are dispersed towards the north by birds or mammals in the northern hemisphere, our findings suggest that they can also be transferred from north to south. Therefore, pathogens of tick-borne diseases that are endemic can be transferred from regions of high to low latitudes. This is an important discovery for understanding the biogeography of I. pavlovskyi and the risk of tick-borne diseases transmitted by I. pavlovskyi.